Fracturing liquid delivery hose for recovery of shale oil &amp; gas, and manufacturing method and co-extrusion mold thereof

ABSTRACT

Provided are a fracturing liquid delivery hose for recovery of shale oil &amp; gas, and manufacturing method and co-extrusion mold thereof. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil &amp; gas according to the present invention includes: ( 1 ) extrusion of a cover layer bearing an adhesive layer; ( 2 ) extrusion of an inner lining bearing the adhesive layer; ( 3 ) physically permeation of the extruded cover layer and the inner lining for standby use; ( 4 ) formation of an enhancement layer; ( 5 ) heating and pressurizing for physical and chemical bonding between the cover layer and the enhancement layer; ( 6 ) turning it over; ( 7 ) heating and pressurizing for physical and chemical bonding between the inner lining and the enhancement layer. In the present invention, the different types of materials may be used for the cover layer and the inner lining, and the cover layer and the inner lining of different materials may be combined for more needs and reduced product cost. The hose is more integral, anti-flexible, long in service life; but also has high resistance to high pressure, high delivering rate, convenient connection, desirable weather- and chemical-resistance, and is suitable for various topographies. In case of no service, it is flat, easily wound up and has low volume during storage and transportation.

BACKGROUND

1. Technical Field

The present invention relates to a fracturing liquid delivery hose forrecovery of shale oil & gas, and manufacturing method and co-extrusionmold thereof, and falls within the field of fluid delivery equipment.

2. Related Art

The hydrofracturing technology is a method only available for commercialrecovery of shale oil & gas at present, where after a high pressureliquid is filled in a bore well and causes a terrane to fracture, apropping agent in the high pressure liquid allows a crack to be hold upand to be a quick permeation channel for oil-gas steering drilling. Thefracturing liquid used in the hydrofracturing method available forrecovery of shale gas essentially includes water, sand and chemicaladditives (salts and some emulsifying agents), with the content of waterand sand being 99% or more. An amount of the fracturing liquid used forexploitation of shale gas is very high, and the fracturing liquid of 4-5million gallons (1 gallon corresponding to about 3.78 L) is required foreach of the shale gas bore wells, to make shale rupture.

Presently, a metal pipe is commonly used for long distance delivery(about 10 miles) in recovery of shale oil & gas, having disadvantages ofa high layout load, difficult layout on topographically complicatedzones such as slope, ravine and pond, and more severely, soil pollutioncaused by water leakage from pipe couplings susceptible to cracking.

SUMMARY

To solve the problems mentioned above, an objective of the presentinvention is to provide a fracturing liquid delivery hose for recoveryof shale oil & gas and manufacturing method and co-extrusion moldthereof, where the hose of the present invention is more integral,anti-flexible, long in service life; but also has high resistance tohigh pressure, high delivering rate, convenient connection, desirableweather- and chemical-resistance, and is suitable for varioustopographies; in case of no service, it is flat, easily wound up and haslow volume during storage and transportation.

The objective is achieved by the technical solutions as follows:

A method for manufacturing the fracturing liquid delivery hose forrecovery of shale oil & gas, including the following steps:

(1) Extrusion of a cover layer bearing an adhesive layer: extruding thecover layer grains and adhesive grains by two extruders into aco-extrusion mold, and subjecting a coextruded laminate layer tocooling, pulling and squashing to give a flat tube i.e. the cover layerbearing the adhesive layer, where the adhesive layer has a thickness of0.10-0.35 mm and the cover layer has a thickness of 0.5-4.0 mm;

(2) Extrusion of an inner lining bearing an adhesive layer: extrudingthe inner lining grains and adhesive grains by two extruders into aco-extrusion mold, and subjecting the coextruded laminate layer tocooling, pulling and squashing to give a flat tube i.e. the inner liningbearing the adhesive layer, where the adhesive layer has a thickness of0.10-0.35 mm and the inner lining has a thickness of 0.5-4.0 mm;

(3) Separate treatment of the intermediates from Step (1) and Step (2)on the surface: immersing it into a solution for physical permeationprior to use, where the solution is formulated from a curing agent andsolvent at a ratio of 10-30:70-90;

(4) Formation of an enhancement layer: weaving a tubular enhancementlayer according to product design specifications;

(5) Bonding between the cover layer and the enhancement layer: pullingthe surface-treated cover layer with the adhesive layer from Step (3)into the tubular enhancement layer, fixing at both ends, passing througha steam of 0.10-0.35 Mpa for 4-10 minutes, prior to cooling with air inplace of steam while maintaining pressure to the desired temperature;

(6) Turnover: turning over the product from Step (5) to exchange itsinner layer for the outer layer;

(7) Bonding between the inner lining and the enhancement layer: pullingthe surface-treated inner lining with the adhesive layer from Step (3)into the product from

Step (6), fixing at both ends, passing through a steam of 0.10-0.35 Mpafor 4-10 minutes, prior to cooling with air in place of steam whilemaintaining pressure to the desired temperature.

In the method for manufacturing the fracturing liquid delivery hose forrecovery of shale oil & gas, the TPU grains or TPU and PVC alloys areused in the cover layer described in Step (1), and the TPU grains orTPU/PVC alloys or PVC or PVC/butyronitrile are used in the inner liningdescribed in Step (2), where in the TPU/PVC alloys, TPU:PVC=100:0-70; inthe PVC/butyronitrile, PVC:butyronitrile=100:0-70; and in Step (1) andStep (2), the cover layer and inner lining grains are extruded attemperature of 150-210° C., and the adhesive grains are extruded attemperature of 140-175° C.

In the method for manufacturing the fracturing liquid delivery hose forrecovery of shale oil & gas, a color concentrate is also added to thecover layer grains and the inner lining grains described in Step (1)and/or Step (2) at 100:(0.5-1.5) mass ratio of the cover layer grains orthe inner lining grains to the color concentrate, and then stirreduniformly and dried.

In the method for manufacturing the fracturing liquid delivery hose forrecovery of shale oil & gas, the enhancement layer described in Step (4)is woven from the Terylene filaments or Nylon filaments or aramid fibersor the blends of Terylene and nylon filaments or aramid fibers.

The method for manufacturing the fracturing liquid delivery hose forrecovery of shale oil & gas further includes rolling pass on the surfaceafter turnover.

The fracturing liquid delivery hose for recovery of shale oil & gas,manufactured in the method, is characterized in that it includes, fromouter to inner: the cover layer, the enhancement layer and the innerlining, where bonding between the cover layer and the enhancement layerand between the enhancement layer and the inner lining are achieved bythe adhesive layer respectively.

In the fracturing liquid delivery hose for recovery of shale oil & gas,the thickness is 0.5-4.0 mm for the cover layer, 1.5-5.0 mm for theenhancement layer, 0.5-4.0 mm for the inner lining and 0.10-0.35 mm forthe adhesive layer.

In the fracturing liquid delivery hose for recovery of shale oil & gas,the enhancement layer woven from ends and picks is tubular.

In the fracturing liquid delivery hose for recovery of shale oil & gas,the copper wire is woven uniformly in axial direction on the enhancementlayer for antistatic effect.

A co-extrusion mold, including: a housing equipped with a shaft therein;a distributor block, provided below the shaft, in the form of frustumfor its lower part, where there is a gap between the shaft and thedistributor block, the distributor block is fixedly connected to thehousing having a first feed inlet connected to the cover layer or innerlining grain extruder, the first feed inlet penetrates through thehousing and is connected fluidly to the gap between the shaft and thedistributor block; a mold case provided outside the distributor block,where there is a gap between the mold case and the distributor block,the mold case is fixedly connected to the housing, the mold case has asecond feed inlet connected to the adhesive extruder, the second feedinlet penetrates through the mold case and is connected fluidly to thegap between the mold case and the distributor block; and a clamping ringprovided between the distributor block and the housing.

Advantageous Effects

1. The fracturing liquid delivery hose for recovery of shale oil & gasaccording to the present invention includes from outer to inner: thecover layer, the enhancement layer and the inner lining, where theadhesive layer is used for bonding between the cover layer andenhancement layer and between the enhancement layer and the inner liningrespectively, the cover layer and the inner lining may be designed fordifferent materials, with the inner lining used with the materialshaving resistance to corrosion of the chemical media and oils and thecover layer used with the materials having resistance to weather, ozone,wear and piercing, thus allowing the advantages of various materials tomaximize. As an embodiment of the present invention, TPU is used in boththe cover layer and the inner lining which are bound to the enhancementlayer by the adhesive agent by physical and chemical cross-linking, andthe hose with peel strength up to 8 KN/M is more integral, remainsstrong bonding after long time service, significantly improving theflexibility and service life of the product. The process according thepresent invention is simple in operation, high in efficiency, high inproductive capacity and low in investment.

2. The hose produced in the method of the present invention is light inweight, desirable in ductility, wear-resistant, corrosion-resistant,weather-resistant, but also may be connected by various standardfasteners, easily wound up, and easily assembled and disassembled. Theturnover process is used for the hose according to the presentinvention, with length of more than 200 meters and inner diameters of200 mm (8″), 250 mm (10″), 300 mm (12″), 400 mm (16″), 600 mm (24″) forvarious specifications.

3. In the present invention, the adhesive layer enables firm bondingbetween the cover layer and the enhancement layer and between the innerlining and the enhancement layer, leading to improved peel strength,more integrity of the hose and improved service life. In the presentinvention, the turnover process is carried out by laminating the coverlayer and the adhesive layer by mechanical co-extrusion, immersing intothe curing agent solution, pulling into the enhancement layer, bonding,turning over, rolling pass; and laminating the inner lining and theadhesive layer by co-extrusion, immersing the curing agent solution,pulling into the cover layer/enhancement layer and bonding at elevatedtemperature and pressure. The process is advantageous in that the coverlayer and inner lining are designed by functions respectively and usedwith different materials, and the operation is easy, with highefficiency.

4. In the present invention, a special co-extrusion mold is designedwith easy operation and high efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of the structure of the co-extrusionmold of the present invention,

where, 1: housing, 2: shaft, 3: clamping ring, 4: distributor block, 5:mold case, 6: first feed inlet, 7: second feed inlet.

DETAILED DESCRIPTION Embodiment 1

The fracturing liquid delivery hose for recovery of shale oil & gasincludes from outer to inner: the cover layer, the enhancement layer andthe inner lining, where bonding between the cover layer and theenhancement layer and between the enhancement layer and the inner liningwere achieved by the adhesive layer respectively.

The thickness was 0.5 mm for the cover layer, 5.0 mm for the enhancementlayer, 4.0 mm for the inner lining, and 0.35 mm for the adhesive layer.

The enhancement layer woven from ends and picks was tubular.

Embodiment 2

This embodiment was different from Embodiment 1 in that, the thicknesswas 4.0 mm for the cover layer, 1.0 mm for the enhancement layer, 4.0 mmfor the inner lining, and 0.10 mm for the adhesive layer. The ends andpicks were used with Nylon.

Embodiment 3

This embodiment was different from Embodiment 1 in that, the thicknesswas 2.5 mm for the cover layer, 3.5 mm for the enhancement layer, 2.5 mmfor the inner lining and 0.25 mm for the adhesive layer. Moreover, twocopper wires were uniformly distributed in axial direction in theenhancement layer. Addition of copper wires enabled antistatic effect.

Embodiment 4

This embodiment was different from the preceding embodiments in that, 8copper wires were uniformly distributed in axial direction in theenhancement layer. It was also possible for 3 or 4 or 5 or 6 or 7 copperwires.

Embodiment 5

The method for manufacturing the fracturing liquid delivery hose forrecovery of shale oil & gas includes the following steps:

(1) Extrusion of a cover layer bearing an adhesive layer: extruding thecover layer grains and adhesive grains by two extruders into aco-extrusion mold, and subjecting a coextruded laminate layer tocooling, pulling and squashing to give a flat tube i.e. the cover layerbearing the adhesive layer, where the adhesive layer had a thickness of0.10-0.35 mm and the cover layer had a thickness of 0.5-4.0 mm;

(2) Extrusion of an inner lining bearing an adhesive layer: extrudingthe inner lining grains and adhesive grains by two extruders into aco-extrusion mold, and subjecting the coextruded laminate layer tocooling, pulling and squashing to give a flat tube i.e. the inner liningbearing the adhesive layer, where the adhesive layer had a thickness of0.10-0.35 mm and the inner lining had a thickness of 0.5-4.0 mm;

(3) Separate treatment of the intermediates from Step (1) and Step (2)on the surface: immersing it into a solution for physical permeationprior to use, where the solution was formulated from a curing agent andethyl acetate at a ratio of 10-30:70-90. In this embodiment, theadhesive grains used were TPU hot melt adhesive, with UB410B fromLubrizol Corp. used in this embodiment, and the curing agent was amaterial named diphenylmethane diisocyanate (MDI), with BASF M20S usedin this embodiment. The curing agent (including an active NCO) may bebound firmly to the Terylene filaments also including hydroxy, byphysical permeation and chemical reaction, at a certain temperature andpressure. Nylon includes aminoisocyanate as active site, which readilyreacts with hydroxy and amino to give carbamate and urea structure,which would also firmly bond together by physical permeation andchemical reaction, at a certain temperature and pressure. The treatedaramid fiber may include amino and isocyanate, which may also firmlybond by physicochemical reaction with the curing agent at a certaintemperature and pressure.

(4) Formation of an enhancement layer: weaving the tubular enhancementlayer according to product design specification:

(5) Bonding between the cover layer and the enhancement layer: pullingthe surface-treated cover layer with the adhesive layer from Step (3)into the tubular enhancement layer, fixing at both ends, passing througha steam of 0.10-0.35 Mpa for 4-10 minutes, prior to cooling with air inplace of steam while maintaining pressure to the desired temperature;

(6) Turnover: turning over the product from Step (5) to exchange itsinner layer for the outer layer;

(7) Rolling pass on the product from Step (6).

(8) Bonding between the inner lining and the enhancement layer: pullingthe surface-treated inner lining with the adhesive layer from Step (3)into the product from Step (7), fixing at both ends, passing through asteam of 0.10-0.35 Mpa for 4-10 minutes, prior to cooling with air inplace of steam while maintaining pressure to a desired temperature.

In this embodiment, the cover layer and the inner lining were used withTPU (polyether type, R185A from Lubrizol Corp.).

Embodiment 6

This embodiment was different from Embodiment 5 in that, the cover layerwas used with TPU of polyether type (R185A from Lubrizol Corp.), theinner lining was used with liner PVC (medical grade PVC from ShanghaiChloro-Alkali Chemical Co., Ltd.) or PVC/butyronitrile (medical gradePVC from Shanghai Chloro-Alkali Chemical Co., Ltd., LG830 from LGchemical as powdered PNBR, the mass ratio of PVC to powderedbutyronitrile=100:0-70).

Embodiment 7

This embodiment was different from Embodiment 6 in that, the enhancementlayer described in Step (4) was woven from Terylene filaments or Nylonor aramid fibers.

Embodiment 8

A co-extrusion mold, as shown in FIG. 1, including: a housing 1 equippedwith a shaft 2 therein; a distributor block 4, provided below the shaft,in the form of frustum for its lower part, where there was a gap betweenthe shaft and the distributor block, the distributor block was fixedlyconnected to the housing having a first feed inlet 6 connected to thecover layer or inner lining grain extruder, the first feed inletpenetrated through the housing and was connected fluidly to the gapbetween the shaft and the distributor block; a mold case 5 providedoutside the distributor block, where there was a gap between the moldcase and the distributor block, the mold case was fixedly connected tothe housing, the mold case had a second feed inlet 7 connected to theadhesive extruder, the second feed inlet penetrated through the moldcase and was connected fluidly to the gap between the mold case and thedistributor block. In operation, the shaft rotated, and TPU flew outalong the gas between the shaft and the distributor block while theadhesive entered through the second feed inlet and flew out along thegap between the distributor block and the mold case, due to fluidconnection of the first feed inlet connected to the TPU grain extruderto the gap between the shaft and the distributor block; the distributorblock lower part was provided in the form of frustum such that the gapbetween the TPU extrusion port and the adhesive extrusion port was verysmall, allowing the adhesive to be attached on the outer layer of theTPU tube for the final product obtained at high temperature.

Embodiment 9

In the co-extrusion mold described in Embodiment 8, the clamping ring 3was provided between the distributor block and the housing.

1. A method for manufacturing a fracturing liquid delivery hose for recovery of shale oil & gas, comprising: (1) Extrusion of a cover layer bearing an adhesive layer: extruding the cover layer grains and adhesive grains by two extruders into a co-extrusion mold, and subjecting a coextruded laminate layer to cooling, pulling and squashing to give a flat tube i.e. the cover layer bearing the adhesive layer, wherein the adhesive layer has a thickness of 0.10-0.35 mm and the cover layer has a thickness of 0.5-4.0 mm; (2) Extrusion of an inner lining bearing an adhesive layer: extruding the inner lining grains and adhesive grains by two extruders into a co-extrusion mold, and subjecting the coextruded laminate layer to cooling, pulling and squashing to give a flat tube i.e. the inner lining bearing the adhesive layer, wherein the adhesive layer has a thickness of 0.10-0.35 mm and the inner lining has a thickness of 0.5-4.0 mm; (3) Separate treatment of the intermediates from Step (1) and Step (2) on the surface: immersing it into a solution for physical permeation prior to use, wherein the solution is formulated from a curing agent and solvent at a ratio of 10-30:70-90; (4) Formation of an enhancement layer: weaving a tubular enhancement layer according to product design specification; (5) Bonding between the cover layer and the enhancement layer: pulling the surface-treated cover layer with the adhesive layer from Step (3) into the tubular enhancement layer, fixing at both ends, passing through a steam of 0.10-0.35 Mpa for 4-10 minutes, prior to cooling with air in place of steam while maintaining pressure to the desired temperature; (6) Turnover: turning over the product from Step (5) to exchange its inner layer for the outer layer; (7) Bonding between the inner lining and the enhancement layer: pulling the surface-treated inner lining with the adhesive layer from Step (3) into the product from Step (6), fixing at both ends, passing through a steam of 0.10-0.35 Mpa for 4-10 minutes, prior to cooling with air in place of steam while maintaining pressure to a desired temperature.
 2. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 1, wherein: the cover layer described in Step (1) is used with TPU grains or TPU/PVC alloys, the inner lining described in Step (2) is used with TPU grain or TPU/PVC alloys or PVC or PVC/butyronitrile, with TPU:PVC=100:0-70 in the TPU/ PVC alloys and PVC:butyronitrile=100:0-70 in the PVC/butyronitrile.
 3. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 1, wherein in Step (1) and Step (2), the cover layer grains and the inner lining grains are extruded at a temperature of 150-210° C., and the adhesive grains are extruded at a temperature of 140-175° C.
 4. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 1, wherein a color concentrate is added to the cover layer grains and the inner lining grains described in Step (1) and/or Step (2) at 100:(0.5-1.5) mass ratio of the cover layer grains or the inner lining grains to the color concentrate, and then stirred uniformly and dried.
 5. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 1, wherein the enhancement layer described in Step (4) is woven from the Terylene filaments or Nylon filaments or aramid fibers or the blends of Terylene and nylon filaments or aramid fibers.
 6. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 1, further comprising rolling pass on the surface after turnover.
 7. A fracturing liquid delivery hose for recovery of shale oil & gas, manufactured by the method according to claim 1, comprising from outer to inner: a cover layer, an enhancement layer and an inner lining, wherein bonding between the cover layer and the enhancement layer and between the enhancement layer and the inner lining are achieved by an adhesive layer respectively.
 8. The fracturing liquid delivery hose for recovery of shale oil & gas according to claim 6, wherein the thickness is 0.5-4.0 mm for the cover layer, 1.5-5.0 mm for the enhancement layer, 0.5-4.0 mm for the inner lining and 0.10-0.35 mm for the adhesive layer.
 9. The fracturing liquid delivery hose for recovery of shale oil & gas according to claim 1, wherein the enhancement layer woven from ends and picks is tubular.
 10. A co-extrusion mold, comprising: a housing equipped with a shaft therein; a distributor block, provided below the shaft, in the form of frustum for its lower part, wherein there is a gap between the shaft and the distributor block, the distributor block is fixedly connected to the housing having a first feed inlet connected to the cover layer or inner lining grain extruder, the first feed inlet penetrates through the housing and is connected fluidly to the gap between the shaft and the distributor block; a mold case provided outside the distributor block, wherein there is a gap between the mold case and the distributor block, the mold case is fixedly connected to the housing, the mold case has a second feed inlet connected to the adhesive extruder, the second feed inlet penetrates through the mold case and is connected fluidly to the gap between the mold case and the distributor block; and a clamping ring provided between the distributor block and the housing.
 11. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 2, wherein in Step (1) and Step (2), the cover layer grains and the inner lining grains are extruded at a temperature of 150-210° C., and the adhesive grains are extruded at a temperature of 140-175° C.
 12. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 2, wherein a color concentrate is added to the cover layer grains and the inner lining grains described in Step (1) and/or Step (2) at 100:(0.5-1.5) mass ratio of the cover layer grains or the inner lining grains to the color concentrate, and then stirred uniformly and dried.
 13. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 2, wherein the enhancement layer described in Step (4) is woven from the Terylene filaments or Nylon filaments or aramid fibers or the blends of Terylene and nylon filaments or aramid fibers.
 14. The method for manufacturing the fracturing liquid delivery hose for recovery of shale oil & gas according to claim 2, further comprising rolling pass on the surface after turnover.
 15. The fracturing liquid delivery hose for recovery of shale oil & gas according to claim 14, wherein the thickness is 0.5-4.0 mm for the cover layer, 1.5-5.0 mm for the enhancement layer, 0.5-4.0 mm for the inner lining and 0.10-0.35 mm for the adhesive layer.
 16. The fracturing liquid delivery hose for recovery of shale oil & gas according to claim 2, wherein the enhancement layer woven from ends and picks is tubular. 